Multimodal, live imaging of peri-infarct depolarisation (PID) during global forebrain ischemia in the rat cerebral cortex

Abstract

Event Abstract Back to Event Multimodal, live imaging of peri-infarct depolarisation (PID) during global forebrain ischemia in the rat cerebral cortex Z. Bere1*, A. Kulmány1, 2, T. P. Obrenovitch3, F. Bari4 and E. Farkas1, 2 1 University of Szeged, Department of Medical Physics and Informatics, Hungary 2 University of Szeged, Department of Physiology, Hungary 3 University of Bradford, Division of Pharmacology, School of Life Sciences, United Kingdom 4 University of Szeged, Department of Medical Physics and Informatics, Hungary PID and associated changes in cerebral blood flow (CBF) spontaneously occur in the cortex during cerebral ischemia and may contribute to the extension of brain infarcts. We have set out to characterize PID-related changes in membrane potential and hemodynamic variables in rat cerebral cortex. In anesthetized, male Sprague-Dawley rats (n=13) a closed cranial window was mounted over the parietal bone and loaded with voltage sensitive (VS) dye. The left femoral artery and vein were cannulated for the monitoring of mean arterial pressure (MAP) and for blood withdrawal. Global forebrain ischemia was induced by bilateral common carotid artery occlusion combined with subsequent hypovolemic hypotension (MAP<40 mmHg). Using selected illuminations we acquired synchronous changes in membrane potential (VS dye method); cerebral blood volume with green (540–550 nm); hemoglobin saturation with red (620–640 nm) illumination, and CBF by laser speckle contrast imaging. PID occurred at a MAP value of 41.2±3.7 mmHg and at a CBF value of 43.4±4.9%. In most cases the depolarization was not followed by the recovery of membrane potential, and these events were associated with CBF reduction (19±3.6%). In conclusion, PID appears to generate at the lower limit of the autoregulatory range of CBF, originates at a focus with high vulnerability to ischemia, and propagates similar to that known for cortical spreading depression. PID associated CBF responses most often display inverse neurovascular coupling. Acknowledgements (NFM, NNF 78902) (OTKA, K81266) Keywords: disorders, Neuroscience Conference: 13th Conference of the Hungarian Neuroscience Society (MITT), Budapest, Hungary, 20 Jan - 22 Jan, 2011. Presentation Type: Abstract Topic: Disorders Citation: Bere Z, Kulmány A, Obrenovitch TP, Bari F and Farkas E (2011). Multimodal, live imaging of peri-infarct depolarisation (PID) during global forebrain ischemia in the rat cerebral cortex. Front. Neurosci. Conference Abstract: 13th Conference of the Hungarian Neuroscience Society (MITT). doi: 10.3389/conf.fnins.2011.84.00095 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 03 Mar 2011; Published Online: 23 Mar 2011. * Correspondence: Dr. Z. Bere, University of Szeged, Department of Medical Physics and Informatics, Szeged, Hungary, berezsofia@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Z. Bere A. Kulmány T. P Obrenovitch F. Bari E. Farkas Google Z. Bere A. Kulmány T. P Obrenovitch F. Bari E. Farkas Google Scholar Z. Bere A. Kulmány T. P Obrenovitch F. Bari E. Farkas PubMed Z. Bere A. Kulmány T. P Obrenovitch F. Bari E. Farkas Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.